Method of production polyamide resin wherein carboxylic acid-activator and/or inorganic salt is present in reaction system therefor

Abstract

A method of producing a polyamide resin by reacting with at least one diamine compounds at least one linear polyester resin consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g, so that the at least one diol component of the linear polyester resin is substituted by the diamine compound, resulting in the polyamide resin as a reaction product, wherein the improvement comprises: at least one of a carboxylic acid-activator and an inorganic salt being present in a reaction system of the linear polyester resin and the diamine compound.

What is claimed is:  
     
       1. A method of producing a polyamide resin by reacting with at least one diamine compound, at least one linear polyester resin consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g, so that said at least one diol component of said linear polyester resin is substituted by said diamine compound, resulting in said polyamide resin as a reaction product, wherein the improvement comprises: 
       at least one of a carboxylic acid-activator, in an amount of 0.01-0.5 mol per 1 mol of said linear polyester resin as calculated in the repeating unit thereof, and an inorganic salt, formed of metal ions selected from the group consisting of an alkaline metal ion, alkaline earth metal ion, transition metal ion and anions selected from the group consisting of chloride ions, bromide ions, and iodide ions, being present in a reaction system of said linear polyester resin and said diamine compound said linear polyester resin reacting with said diamine compound in a reaction medium comprising at least one solvent selected from aprotic solvents.  
     
     
       2. A method according to  claim 1  further comprising a step of effecting polycondensation in a solid state or molten state on said reaction product. 
     
     
       3. A method according to  claim 1 , wherein said inorganic salt is used in an amount of 0.1-30 parts by weight per 100 parts by weight of said aprotic solvent. 
     
     
       4. A method of producing a polyamide resin by reacting with at least one diamine compound, at least one thermoplastic polyalkylene terephthalate resin consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g, so that said at least one diol component of said thermoplastic polyalkylene terephthalate resin is substituted by said diamine compound, resulting in said polyamide resin as a reaction product, wherein the improvement comprises; 
       at least one of a carboxylic acid-activator and an inorganic salt, said inorganic salt being formed of metal ions selected from the group consisting of an alkaline metal ion, alkaline earth metal ion, transition metal ion and anions selected from the group consisting of chloride ions, bromide ions, and iodide ions, being present in a reaction system of said thermoplastic polyalkylene terephthalate resin and said diamine compound;  
       the method further comprising a step of melting and kneading reaction materials which include said thermoplastic polyalkylene terephthalate resin, said diamine compound, and said at least one of said carboxylic acid-activator and said inorganic salt.  
     
     
       5. A method according to  claim 4 , wherein said thermoplastic polyalkylene terephthalate resin is a polyethylene terephthalate resin. 
     
     
       6. A method of producing a polyamide resin by reacting with at least one diamine compound, at least one thermoplastic polyalkylene terephthalate resin consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g, so that said at least one diol component of said thermoplastic polyalkylene terephthatate resin is substituted by said diamine compound, resulting in said polyamide resin as a reaction product, wherein the improvement comprises: 
       at least one of a carboxylic acid-activator and an inorganic salt, said inorganic salt being formed of metal ions selected from the group consisting of an alkaline metal ion, alkaline earth metal ion, transition metal ion and anions selected from the group consisting of chloride ions, bromide ions, and iodide ions, being present in a reaction system of said thermoplastic polyalkylene terephthalate resin and said diamine compound;  
       said thermoplastic polyalkylene terephthalate resin being used in a powder form and reacting with said diamine compound at a temperature in a range between a temperature not lower than a melting point of said diamine compound and a temperature not higher than a melting point of said thermoplastic polyalkylene terephthalate.  
     
     
       7. A method according to  claim 6 , wherein said thermoplastic polyalkylene terephthalate resin is a polyethylene terephthalatc resin. 
     
     
       8. A method according to  claim 4 , wherein said diamine compound is used in an amount of 0.05-1.5 mol per 1 mol of said thermoplastic polyalkylene terephthalate resin as calculated in the repeating unit thereof. 
     
     
       9. A method according to  claim 4 , wherein said carboxylic-acid activator is used in an amount of 0.001-0.2 mol per 1 mol of said thermoplastic polyalkylene terephthalate resin as calculated in the repeating unit thereof. 
     
     
       10. A method according to  claim 4 , wherein said inorganic salt is used in an amount of 0.01-10 parts by weight per 100 parts by weight of said thermoplastic polyalkylene terephthalate resin. 
     
     
       11. A method according to  claim 4 , wherein said step of melting and kneading said reaction materials is effected while adding said diamine compound to said thermoplastic polyalkylene terephthalate resin at least two times until an amount of said diamine compound added to said thermoplastic polyalkylene terephthalate resin is equal to a required amount for reaction with said thermoplastic polyalkylene terephthalate resin. 
     
     
       12. A method according to  claim 4 , wherein said step of melting and kneading said reaction materials is effected after mixing said thermoplastic polyalkylene terephthalate resin in a powder form with said diamine compound, and heating said reaction materials at a temperature in a range between a temperature not lower than a melting point of said diamine compound and a temperature not higher than a melting point of said thermoplastic polyalkylene terephthalate resin, so as to effect a preliminary reaction between said thermoplastic polyalkylene terephthalate resin and said diamine compound. 
     
     
       13. A method according to  claim 4 , wherein said step of melting and kneading said reaction materials is effected in an atmosphere of an inert gas. 
     
     
       14. A method according to  claim 6 , wherein said thermoplastic polyalkylene terephthalate resin reacts with said diamine compound in an atmosphere of an inert gas. 
     
     
       15. A method according to  claim 1 , wherein said linear polyester resin is a thermoplastic polyalkylene terephthalate resin. 
     
     
       16. A method according to  claim 15 , wherein said thermoplastic polyalkylene terephthalate resin is a polyethylene terephthalate resin. 
     
     
       17. A method of producing a polyamide resin comprising the steps of: 
       reacting with at least one diamine compound, at least one linear polyester resin consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g, said linear polyester resin and said diamine compound being reacted in a reaction medium comprising at least one solvent selected from aprotic solvents, so that said at least one diol component of said linear polyester resin is substituted by said diamine compound, so as to provide a reaction product;  
       adding at least one of a carboxylic acid-activator and an inorganic salt to said reaction product; and  
       effecting polycondensation in a solid state or molten state on said reaction product to which at least one of said carboxylic acid-activator and said inorganic salt has been added.  
     
     
       18. A method according to  claim 17 , wherein said carboxylic acid-activator is used in an amount of 0.1-20 parts by weight per 100 parts by weight of said reaction product. 
     
     
       19. A method according to  claim 17 , wherein said inorganic salt is uded in an amount of 0.1-10 parts by weight per 100 parts by weight of said reaction product. 
     
     
       20. A method according to  claim 17 , wherein said linear polyester resin is a thermoplastic polyalkylene terephthalate resin. 
     
     
       21. A method according to  claim 20 , wherein said thermoplastic polyalkylene terephthalate resin is a polyethylene terephthalate resin. 
     
     
       22. A method of producing a polyamide resin by reacting with at least one diamine compound, at least one linear polyester resin consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g, wherein the improvements comprises: 
       said diamine compound being added to said linear polyester resin at least two times until an amount of said diamine compound added to said linear polyester resin is equal to a required amount for reaction with said linear polyester resin while a mixture of said linear polyester resin and said diamine compound is melted and kneaded.  
     
     
       23. A method according to  claim 22 , wherein said mixture of said linear polyester resin and said diamine compound is melted and kneaded in an atmosphere of an inert gas. 
     
     
       24. A method according to  claim 22 , wherein said diamine compound is used in an amount of 0.05-1.5 mol per 1 mol of said linear polyester resin as calculated in the repeating unit thereof. 
     
     
       25. A method of producing a polyamide resin by reacting with at least one diamine compound, at least one linear polyester resin consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g, said method comprising the steps of: 
       mixing said linear polyester resin in a powder form with said diamine compound;  
       heating a mixture of said linear polyester resin and said diamine compound at a temperature in a range between a temperature not lower than a melting point of said diamine compound and a temperature not higher than a melting point of said linear polyester resin, so as to effect a preliminary reaction between said linear polyester resin and said diamine compound; and  
       melting and kneading a reaction product obtained by said preliminary reaction for further proceeding a reaction between said linear polyester resin and said diamine compound.  
     
     
       26. A method according to  claim 25 , wherein said step of melting and kneading said reaction product obtained by said preliminary reaction is effected in an atmosphere of an inert gas. 
     
     
       27. A method according to  claim 25 , wherein said diamine compound is used in an amount of 0.05-1.5 mol per 1 mol of said linear polyester resin as calculated in the repeating unit thereof. 
     
     
       28. A method of producing a polyamide resin by reacting with at least one diamine compound, at least one linear polyester resin consisting of at least one dicarboxylic acid component and at least one diol component and having an intrinsic viscosity of not less than 0.2 dl/g, said method comprising the steps of: 
       mixing said linear polyester resin in a powder form with said diamine compound; and  
       heating a mixture of said linear polyester resin and said diamine compound at a temperature in a range between a temperature not lower than a melting point of said diamine compound and a temperature not higher than a melting point of said polyester resin.  
     
     
       29. A method according to  claim 28 , wherein said step of heating said mixture is effected in an atmosphere of an inert gas. 
     
     
       30. A method according to  claim 28 , wherein said diamine compound is used in an amount of 0.05-1.5 mol per 1 mol of said linear polyester resin as calculated in the repeating unit thereof.